Mission: Lifeline Frequently Asked Questions

The heart muscle needs oxygen to survive. A heart attack typically occurs when the blood flow that brings oxygen to the heart muscle is severely reduced (non-STEMI heart attack) or cut off completely (STEMI heart attack). Blockage occurs when coronary arteries that supply blood to the heart become thicker and harder over time from a buildup of fat, cholesterol and other substances collectively called "plaque." This slow process is known as atherosclerosis. If plaque in a heart artery breaks, a blood clot forms around the plaque. This clot can block the artery and shut off blood flow to the heart muscle. When the heart muscle is starved for oxygen and nutrients, it is called ischemia. When damage or death of part of the heart muscle occurs as a result of ischemia, it is called a heart attack, or more formally a coronary attack or myocardial infarction (MI).

STEMI is an abbreviation for ST-elevation myocardial infarction, a severe heart attack caused by a prolonged period of blocked blood supply that affects a large area of the heart. Over 250,000 people suffer from a STEMI heart attack each year, which carries a substantial risk of death and disability.

Many people such as women and those with chronic conditions such as diabetes may not experience the typical symptoms of a heart attack. Typical symptoms of a heart attack include the presence of one or more of these symptoms may mean a heart attack is occurring:

Chest discomfort The majority of heart attacks involve discomfort in the center of the chest that lasts for more than a few minutes or that goes away and returns. This discomfort may feel like pressure, squeezing, fullness or pain

Discomfort in other areas of the upper body Symptoms of a heart attack can include pain or discomfort in one or both arms, the back, neck, jaw or stomach.

Shortness of breath This symptom may occur before, with or without chest discomfort.

Other symptoms Additional signs of a heart attack include cold sweats, nausea and light-headedness.

Artery-opening treatments work best when administered quickly after a heart attack: within 30 minutes for clot-busting drugs and within 90 minutes for percutaneous coronary intervention (PCI), the surgical method of restoring blood flow that is preferred for STEMI patients. Quick response increases your likelihood for positive outcomes.

Emergency medical service (EMS) personnel bring medical care to you, typically an hour faster than for those patients who don't arrive at the hospital in an ambulance. EMS is equipped with oxygen, medication and the means to restart a heart that is no longer beating. Furthermore, more and more ambulances will be equipped with 12-lead electrocardiograms (ECG), which are used to help determine what kind of heart attack you are having so they can make decisions on the hospital that can provide you with the best care. Non-STEMI patients can be treated at the local non-PCI hospital, but STEMI patients receive the best level of care at PCI-capable hospitals.

While most of the 865,000 heart attacks that occur each year are non-ST elevation heart attacks, the nearly 250,000 patients who suffer ST-elevation heart attacks (STEMIs) have an emergent need; they can benefit greatly by having their potential heart damage reduced if their blocked artery is opened in time. STEMI heart attacks carry a substantial risk of death and disability and call for a quick response by many individuals and systems. Although Mission: Lifeline is focusing on improving the system of care for the nearly 250,000 patients who suffer from a STEMI, improving that system will ultimately improve care for all heart attack patients.